But as a new exhibition of unseen Beatles photos goes on display in London, one of their closest pals has revealed how it could have been over before it all began.

Speaking at a huge Fab Four fan fest in New Jersey, Blaenau Gwent-born actor Victor Spinetti described the day he averted disaster and saved their drummer Ringo Starr from drowning.

“It was the first scene we filmed for the movie Help! in 1965 and it was nearly the end for The Beatles,” said Spinetti, the flamboyant Cwm boy who was the only actor to star in all four of the band’s legendary films.

“I was in the Bahamas playing this mad scientist trying to steal a priceless ceremonial ring that Ringo’s wearing, and he was meant to escape by jumping from my yacht into the water.

“So he dives off but quickly comes straight back out shivering because it was freezing and there were shark nets everywhere – it was actually very dangerous,” he added.

“But something went wrong and they had to take shot again, so in he dived once more.

“The third time he was being dried off with a hairdryer and he said: ‘Oh, Victor, I don’t want to do this again’. I asked why and he replied, ‘Because I can’t bloody swim.’

“Can you believe that?” spluttered Victor, 75.

“He could have drowned there and then. So I waved my arms and shouted to the film crew, ‘He can’t swim!’”

Having stopped the shoot Spinetti turned his attention back to the still soaking sticksman.

“I asked him why he’d done it and he said to me, ‘Well, when the director says, ‘Action,’ you’ve got to do it, haven’t you?’”

Spinetti remembered first meeting The Beatles two years before that when George Harrison and John Lennon turned up to watch his Tony-winning performance in the hit stage musical Oh! What A Lovely War.

“George Harrison said to me: ‘You have to be in all our movies because my mum fancies you’,” he laughed, recalling that the Mersey lads were nothing like the serious thespian company he was used to keeping.

“I recall in Help! having to say the line, ‘With this ring, I could rule the world,’ and the four of them lying on the floor beside me screaming with laughter and stoned out of their minds.

“So they had to quickly put the camera close up on me to keep the film going. But that’s ok. That’s what I was there for.”

His skill for keeping a straight face was something that also came in handy on later Fab Four films like Hard Day’s Night, where he played a nervous TV producer.

“I didn’t prepare for the part, I just became it, threw myself into it,” said Victor. “You have to keep a focus going because I knew that the boys would not keep to the script – and they certainly didn’t!

“So I simply kept believing that I was this director and, in fact, in one of the out-takes I remember saying, ‘I am the director,’ and John Lennon replying, ‘You’re not a director. You’re Victor Spinetti playing a part.’

“But I said, ‘But I have an award on the wall in my office,’ to which John answered: ‘Victor, you haven’t even got a dressing room.’”

Victor and the Beatles struck up such a rapport that they’d request him personally every time they started a new project, such as when they were about to start filming Magical Mystery Tour, their first film following the death of manager Brian Epstein in August 1967. The film came in for a lot of stick from fans and critics for it’s undisciplined experimentalism.

“People forget that it was before Monty Python, before a lot of those shows,” said Spinetti defending the freewheeling, spaced-out production.

“John rang me up and said, ‘We’re gonna direct our own film and you’ve got to be in it.’

“He said, ‘We’ve got no f****** script but we want you to do that drill sergeant thing you did in Oh! What a Lovely War’.”

He even turned up on the 1967 Beatles Christmas record. “That’s right, I was tap dancing!” he said.

“John used to invite me up to the studios and I’d say, ‘I don’t want to bother you when you’re working.’

“And he laughed and said, ‘Vic, it’s only the f****** bores that turn up!’”

And the admiration went both ways.

“Flying to the Bahamas for Help! we landed in New York to refuel.

“Suddenly this policeman came on board and said: ‘Is there a Mr Spinetti on this plane?’

“John shouted: ‘They’re deporting you, you’ve been thrown off!’ but the policeman explained, ‘Come to the door of the plane please sir, your fan club is waiting.’

“And it was true. I walked to the door of the plane and I received jelly babies and teddy bears – The Beatles were absolutely astonished.

“After that they became card-carrying members of the Victor Spinetti Fan Club Of America,” he laughed.

The Getty Images Gallery’s collection marking the 40th anniversary of The Beatles’ last live performance on the roof of the Apple Building, Savile Row, will be on display at the Movieum of London in County Hall until July 30.